1. Field of the Invention
The invention relates to a device for the merging of a first list of first elements which is ordered according to a first linear ordering criterion with a second list of second elements which is ordered according to a second linear ordering criterion in order to form a result list of third elements which is ordered according to a third linear ordering criterion. The result list consists of representations of elements of the first list and the second list. Each element of each of the lists contains a quantitative term and ordering is performed on the basis of the value of this term; consequently, relationships also exist between the first, the second and the third ordering criteria as will be explained hereinafter. The term may be explicitly contained in the element, or alternatively implicitly. When the date of birth of a person is explicitly given, the age is implicitly given. Each element may contain further data. When the elements are merged, the information contained therein can be processed in different ways, but this will not be considered herein. There are four linear ordering criteria, that is to say smaller than, smaller than or equal to, larger than, and larger than or equal to (each time a relationship between a preceding element and a later element of the list). The first two criteria have the same ordering direction, and so have the last two criteria. Representation is to be understood to mean herein that each first or second element has one representative third element. However, in some cases it is advantageous for there to be only one representative element for two first elements having the same term value, two second elements having the same term value or a first element and a second element having the same term value. Thus, several possibilities exist which all constitute a representation function.
2. Description of the Prior Art
A device of the kind set forth is known from U.S. Pat. No. 4,276,611 which is assigned to the assignee of the present application, which device will be described in greater detail hereinafter. The known device may be constructed as a fast device, but requires an extensive, distributed processing capability for the list elements.